1. Field of the Invention
This invention relates in general to hand tools for carpenters and in particular to a vise for supporting and transporting thin objects such as doors.
2. Description of the Prior Art
There are no devices widely in use for supporting and transporting doors. Normally a door to be hung is carried by hand or on some sort of cart to the door frame. The carpenter usually balances the door on its edge to cut the mortices for the hinges and latching mechanism. Balancing the door is an awkward task. ALso, hand carrying large doors is difficult and may be dangerous because of their weight and cumbersomeness.
Proposals have been made in the patented art for devices that will support a door on its edge while performing morticing operations. U.S. Pat. Nos. 342,187; 763,941; 1,042,232; and 1,715,722 all show vises for supporting doors. Basically, each shows a pair of jaws hinged together and urged apart from each other by a spring. The weight of the door overcomes the spring, drawing the jaws into contact with the door to support the door on its edge.
One disadvantage of these devices is that the door still must be hand carried to the point where it will be installed. The door is placed in the vise at that point. Another disadvantage is that except for U.S. Pat. No. 1,715,222, the jaws are spaced apart a fixed distance so that they will work best only with a single door thickness. If other sizes are used, the wrong thickness would provide inadequate support. U.S. Pat. No. 1,715,222 discloses adjustable jaws to vary the width, but the adjustment requires utilizing a screwdriver to loosen and retighten two screws for each change, thus is inconvenient.
There are, of course, many devices mounted on wheels for transporting goods, some of which are proposed specifically for doors. For example, see U.S. Pat. Nos. 4,138,099; 3,881,662; and 3,643,935. None of these, however, utilize the vise system as shown in the prior patents, wherein support is provided merely through the weight of the door. Rather, various clamping devices have to be tightened.